How can I light an object for a turntable animation?
One method is to add multiple spotlights surrounding the scene: 

Since World light comes from all directions, Another method is to change the world color and increase the World light strength:






You can also experiment with different types of lights and angles to get the results you are looking for.

Here is the Wolrd lighting + 4 point lights plus a 3d mesh put in the middle:

Each light is 150w and the world lighting is pure white with a strength of 0.4.